Presets :
1. Default
This preset has the slightest performance impact, but with almost unnoticable changes.
2. Natural
This preset makes the game looks more natural with some changes in Shadow and Brightness, heavy performance impact.
3. Smartly Saturated (My Favorite!)
This preset saturates image smartly according to its normal saturation. Suitable for just playing around in the game with moderate performance impact.
4. PhotoRealistic
Makes the game looks more PhotoRealistic. Suitable for making a preview of a mod with the heaviest performance impact.

Credits all goes to the SweetFX creators.

Minimum Spec :
Any PC that can do 50FPS(Or more) in GTA IV's benchmark.

Any questions, feel free to contact me!

P.S : This is NOT an ENB.
P.P.S : Use DKT70's HD Roads for better visuals.
P.P.P.S : The screenshots was taken using the "Smartly Saturated." preset.
P.P.P.P.S : I got the idea from this mod : http://www.gta4-mods.com/misc/amazing-performance-and-graphics-v-34-f23827 Replaces: Graphics